Compressed paper article



` sept. 1o, '1935.

CQK. DUNLAP MPRESSED PAPER ARTICLE Filed Nov.. 3. 1934 Patented Sept. 10, 1935 PATENT OFFICE COMPRESSED PAPER. ARTICLE Charles K. Dunlap, Hartsville, S. C., assignor to Sonoco Products Company, Hartsville, S. C., a corporation of South Carolina Application November 3, 1934, Serial No. 751,403

TC'laims.

A The present invention relates to paper articles of manufacture and particularly toarticles having conical walls of compressed paper.

In my copending application, Serial No. 619,753,

filed June 28, 1932, is disclosed and claimed a method of fabricating paper articles of various types. In practicing the method a series of generally cylindrical paper laminations or windings of diiferent diameters are arranged concentricall0 ly about a common axis to form a blank and the lank is thereafter subjected to heavy pressure by means of similar coaxial conical dies. When submitted to this pressure each lamination or winding of the bla-nk is caused to laterally interlock with adjacent laminations to form a rigid conical structure. The article thus formed may comprise, for example, a base fora bobbin, of which large numbers are used in the textile industry, or it may comprise merely one portion of a paper article having other uses. Thus dishes may be constructed in accordance with the novel process, or ower pots, or other analogous articles. Generally a binding substance is added to the paper blank before the pressure is applied,

which binding substance may be shellac, bake-- lite, parain or the like, thus creating an article which is impervious to water and which has smooth hard surfaces. Even without the addition of the binding substance, however, the article soproduced will have suiiicient mechanical strength to render it useful for many purposes.

In the accompanying drawing are illustrated, by way. of example, several of the novel articles, but it will be appreciated by those skilled in the art that many other similar articles may be devised, having many diierent uses throughout the arts. In each case however the article will have a conical wall comprising compressed paper rings, laminations or windings, each ring laterally interlocking with adjacent rings so that the resulting wall .possesses great mechanical strength. By the use of paper in its production an article will result which is of light weight for its volume, is inexpensive, is rugged and durable in that it will not break as a result of shocks in handling and which may be readily 'f decorated or rendered ornamental by the use of many different colorings or markings. i, In the drawing: f il Figure 1 is a longitudinal section through a bobbin the base of which embodies the invention, being formed of coaxial rings of paper which laterally interlocky Figure 2 is a perspective view of the blank invention; 5

Figure 4 is a perspective view of the blank from which the article in Figure 3 is formed; and 'Figure 5 is a view, partially in section and partially in elevation, of a flower pot embodying the. invention. l0

The bobbin illustrated in section' in Figure l. comprises the tubular thread core supporting portion I0 and the frusto conical base II. Base II is provided with a central cylindrical aperture I2 which closely engagesl the cylindrical 1:,

outer surface of tube III. The lower end of the tube is headed over at I3 and -the two members are preferably secured together by a suitable adhesive substance.

The base II comprises a plurality of rings I4 20 the upper and lower edge surfaces -of which lie respectively in the conical upper and lower sur faces of the base. These rings interlock laterally as shown, each ring having irregular lateral protuberances which t snugly into correspondingly 25 shaped recesses formed in the adjacent ring, lateral interlocking of the rings being brought about by axial compression of a. blank such as indicated in Figure 2 and in the manner fully set forth in my copending application above re- 30 ferred to. 'I'he base I I may be impregnated with shellac, bakelite, parailn or other such substance, giving it smooth surfaces and imparting increased hardness and weight. It will be noted from Figure 2 that the blank comprises a series of con- `35 centric paper rings I5 which are equal in height. Each of these rings may comprise several Windings of paper secured together by an adhesive, as Iis the case where the blank is formed by transversely cutting through a plurality of nested 40 waste textile cones. Or the rings may be formed in other ways, as by transversely severing paper cylinders of different diameters and thereafter nesting the several resulting cylindrical sections. The paper used in the formation of an article 45 such as illustrated at II in Figure l is preferably soft but harder papers may be utilized if suillcient 'pressures are obtainable for the operation ofthe dies.

The article illustrated in Figure 3 includes an 50 annular edge portion I6, a central portion I'I and a conical wall I8 connecting theseat portions. It is formedfrom a blank such as illustrated in Figurefi and in this figure the blank is seen to comprise a continuous winding of relatively thin 55 paper, the blank being impregnated with a binding substance prior to compression or not as desired. The heavy pressure exerted by the dies axially of the blank causes each winding ofpaper to be laterally deected, wrinkled, or distorted and the distortions are suiciently great as to cause each such winding to positively interlock with the next adjacent winding thus providing an article the frusto conical wall of which possesses great resistance to axial compression. By incorporating a suitable binding substance the article may be given increased weight and hardness.

The flower pot illustrated in Figure 5 may also be formed by the novel process, its flat annular upper edge portion I9 comprising a plurality of windings which are laterally interlocked due to axial compression, the windings which comprise the bottom 20 being likewise interlocked. AThe irusto conical wall portion 2| comprises a plurality of windings each of which has been rendered slightly conical and laterally distorted so that the laterally projecting wrinkles of each winding project into recesses in adjacent windings. The ower pot may have a relatively thin wall and in the axial compression of the blank no binding substance may be utilized, the completed flower pot being coated after completion with paint or lacquer to prevent the penetration of moisture and to enable it to present an ornamental appearance.

Many other objects embodying the invention may be devised, as will be apparent. In each instance however the article will include a conical wall comprising a plurality of windings of paper which have been caused to laterally interlock shortening of the paper rings or windings is slight. In practically every instance also the paper rings or windings are rendered slightly conical due to the action of the conical dies utilized in the formation of the article. In some instances the individual rings may be rendered very perceptively cone shaped, as in the form of the linvention illustrated in Figure l. During the compression operation the convex conical die naturally tends to spread the annular edge portions of the rings with which it contacts and the concave die to contract or inwardly incline the opposite edge portions or margins.

The paper used in the formation of the rings may be relatively thin or relatively thick and may be either soft and porous or relatively hard" and non-porous depending upon the nature of the article to be fabricated and upon whether o'rnot a binding substance is to be employed. While in the appended claims the several paper windings which together form the conical or frusto conical wall of the article are defined as coils, it will be appreciated that these windings may either be truly cylindrical members coaxially arranged, as in the case where blanks, such as shown in Figure 2 are originally selected, or may comprise single convolutions of an endless strip convolutely wound into the form of a blank such as shown-in Figure 4.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. An article of manufactura-having a conical paper wall comprising coaxial paper coils the width of each of which is less than the axial 5 length of the conical wall and the diameters of which successively decrease toward the apex of the conical wall, each intermediate coil partially overlapping the two coils positioned next adjacent the same and having a laterally protruding porl0 tion which lies within, and closely engages the wall of, a correspondingly shaped recess in one of the next adjacent coils, all of said coils being thus interloeked into an axially rigid conical structure.

2. An article of manufacture having` a conical paper wall comprising coaxial paper coils the width of each of which is less than the axial length of the conical wall and the diameters of which successivelydecrease toward the apex of the conical wall, ,each intermediate coil partially overlapping the two coils positioned'next adjacent the same and having portions which protrude from opposite sides thereof which lie within, respectively, and closely engage the walls of, correspondingly shaped recesses in the two next adjacent coils, all of the coils included in the conical wall being thus interlocked into an axially rigid structure.

3. An article of manufacture having a conical paper wall comprising coaxial paper coils the width of each of which is less than the axial length of the conical wall and the diameters of which successively decrease toward the apex of the conical wall, each intermediate coil partially overlapping the two coils positioned next adjacent the same, and having annular ridge-like portions which protrude from opposite sides thereof and which lie within and closely engage the walls of correspondingly shaped recesses in the two next adjacent coils, all of the coils included in the conical wall being thus interlocked into an axially rigid structure.

4. An article of manufacture including a conical paper wall having smooth coaxial conical surfaces, the wall comprising coaxial paper coils thev width of each of which is less than the axial length of the conical wall and the diameters of which successively decrease toward the apex of the conical wall, each intermediate coil partially overlapping thefl two coils positioned next adjacent the same and having annular portions which protrude from opposite sides thereof and which lie within and closely engage the walls of correspondingly shaped,- recesses in the two next adjacent coils, all of the coils included in the conical wall being Vthus interlocked into an axially rigid structure, the upper and lower-edge surfaces of the several coils being frustoconical and forming portions, respectively, of the smooth conical sur- Yfaces of the wall. Y A5. The combination set forth in claim 4 in which each of the coils which together comprise the conical wall is itself conical in form.

6. The combination s'et forth in claim 4 in which the built-up conical wall terminates at its smaller 6r. end in an axial cylindrical aperture.

7. The combination set forth in claim4in which the conical wall includes a binding substance which assists in maintaining the rigidity of the wall and provides smooth surfaces for the article.

CHARLES K. DUNLAP. 

